Combining ability and heterosis studies in tomato (Solanum lycopersicum L.) under ToLCV disease stress condition

Abstract

The present investigation was carried out by crossing 15 lines (susceptible to ToLCV) with 3 testers (resistant to ToLCV) in line × tester design, the resultant 45 hybrids along with parents were evaluated for combining ability at Botany Garden, Department of Genetics and Plant Breeding, College of Agriculture, Dharwad during Rabi, 2018-19 and also screened for ToLCV resistant. Analysis of variance revealed highly significant differences among all the F1 hybrid means and their respective six parental values for all examined traits and revealed the predominance of non-additive gene action for all the traits. In respect of both gca and sca effects, the parents and hybrids differed significantly. Among the parents, L4, L5, L6, L7 and AVTO-1219 were the best general combiners for yield per plant and other characters under study, and these may be used as valuable donors in the hybridization programme. Among the crosses, L3 × T3, L8 × T1, L13 × T3 and L14 × T2 were the most valuable combiners for yield per plant and other characters under study could be utilized for heterosis breeding programmes. The crosses L3 × T3, L1 × T3 and L7 × T3 exhibited superior mid parent heterosis for yield per plant. Out of 45 hybrids evaluated for performance in leaf curl stress condition under natural condition, five hybrids L6 × T2, L7 × T3, L10 × T2, L12 × T3 and L13 × T3 exhibited moderate resistance reaction.